AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Organic Chemical Composition of Biodiesel Exhaust Particulate Matter Derived from Two Feedstocks: Soybean and Waste Grease
JOHN KASUMBA, Britt Holmén, University of Vermont
Abstract Number: 45 Working Group: Combustion
Abstract Biodiesel use and production has significantly increased in the United States and in other parts of the world in the past decade. This change is driven by energy security and global climate legislation mandating reductions in the use of petroleum-based diesel. Recent air quality research has shown that emission of some pollutants such as CO, particulate matter (PM), SO2, hydrocarbons, and carcinogenic polycyclic aromatic hydrocarbons (PAHs) is greatly reduced with biodiesel. However, studies have also shown that some unregulated emissions, such as gas-phase carbonyls, are increased with biodiesel combustion. Very limited research has been done to investigate the carbonyl emissions in the particle-phase of biodiesel exhaust.
In this study, an Armfield CM-12 automotive diesel engine was used to generate particulate matter from two biodiesel feedstocks (soybean and waste vegetable oil biodiesel). The PM emissions were sampled by a variety of instruments: - engine exhaust particle sizer, EEPS (TSI Inc, Model 3090) for measuring particle size distributions between 5.6 and 560 nm in real-time; Teflon filters for gravimetric mass, and quartz fiber filters (QFF) for chemical analysis of the exhaust PM using gas chromatography mass spectrometry (GCMS). PAHs, carbonyls, and alkanes were quantified in B20 soybean biodiesel (20% soybean biodiesel and 80% petrodiesel, volume/volume) and petrodiesel exhaust PM. Preliminary results show that the total PAHs emissions were reduced by about 2 times with B20 soybean biodiesel, while the particle-phase carbonyl emissions increased by about 2 times with biodiesel. Alkanes were found at 2 – 3 times higher concentrations in petrodiesel exhaust PM than in biodiesel exhaust PM. Biodiesel was also found to have less particle mass than petrodiesel, but the particle number concentrations in biodiesel were higher. Soybean and waste grease biodiesel particle-phase exhaust emissions will be compared.